Photo 2019-04-15 16.35.24.jpg

Almost as bad as it gets. This is a yachts shore power connection. When unplugged the pins are live. A potentially lethal situation.

man with funny wig holding electrical ca

Shore Power Cables & Connections


The problem with shore power is that two different sets of rules apply. The point at which the rules change is the shore power to marina connection. Up to the service bollard normal shore based electrical rules apply. These rules change at the plug. At this point “Small craft - Electrical systems - Alternating current installations (ISO 13297:2012)” take over.

 Most second hand and older boats do not meet the standards.


A quick look around your local marina will show just how bad shore power connections are. So here is a bullet point guide to help you decide if you are safe.

  • Shore power plugs: For most small craft and marinas the standard outlet is the caravan style 16-amp blue socket. These are surprisingly not that waterproof; they are simply splash proof. This is the only caravan type connector you should have in your shore power system. There are many boats especially yachts that have the caravan style sockets as an inlet to the boat. These are simply not suitable for use on a boat. You should never join or extend a shore power cable using this type of connector.  Domestic 13-amp trailing sockets & plugs must never be used as any part of the shore power lead. The connection to the boat should be via a Marine Standard Shore power connector rated at 16 amps and 240 Volts. (Larger boats have 32-amp inlets)

  • Shore power cables: At the very least 2.5mm2 Artic Grade cable should be used. There are other types of high-quality marine cables such as those supplied with the Victron Shore Power Cables. You should not use domestic flex (the white PVC covered stuff) some black rubber cables should be avoided unless they are a marine grade they will; degrade in sunlight very quickly. On American built boats there are problems. The shore power cables and connectors are not suitable for use in Europe. The cables are usually 4mm2 and cannot safely be fitted to 16-amp caravan plugs. If you have an American imported boat the shore power system an on-board AC system must be replaced.

  • RCD protection: The vessel must have an RCCD system fitted. This should trip at 30ma. The shore power bollard should also have an RCCD fitted. My experience is that there are quite a few Marina Bollards where the RCCD does not work. You can test this yourself by pushing the test button if it trips then all is good. If not do not use the Bollard, contact the marina to report the fault. However, as the skipper you have a responsibility to protect yourself and any visitors, so check you have a correctly installed RCDD and that it also works.

  • Galvanic Isolation:  All metal hulled vessels must have an isolation transformer fitted; the use of a Galvanic Isolator (diode type) is also recommended for other vessels. These isolators help reduce galvanic corrosion of your expensive underwater metal bits. It is essential that when the vessel is hauled out these isolators are by passed. On the transformers you will need to open the unit up and fit a special bypass wire. The diode type galvanic isolators should have a wire connected across the terminals.

  • Cables & Jetties: I have never found an idea solution to this one. In an ideal world & certainly in your home marina you should have a shore power cable that is just the right length.  There are two golden rules which you should stick to.  Never coil the cable up. It may look neat but once any heavy loads are connected it will be become hot and the cable will degrade. A randomly strewn cable may not look pretty but at least it is better practise, of course you can argue, quite rightly, that it represents a trip hazard.  The other golden rule is do not loop it around cleats on or off the boat.  Its best to use rope to tie up your boat not shore power cable.


The Victron shore power cables and inlets make a perect and safe connection for shore power. Avialble in 16 & 32 amp variants with different lengths of cable. 

The shore power cable comes in its own carry bag for safe and neat storgae.